Volatile Constituents and Cytotoxic Activity of Khaya grandifoliola and Khaya senegalensis Flower Extracts

ABSTRACTThe volatiles obtained from fresh flowers of Khaya grandifoliola C.DC. and Khaya senegalensis A.Juss. by hydro-distillation method were analyzed by gas chromatography and gas chromatography–mass spectrometry. Sesquiterpenes represent 86.32% and 80.86% of the identified volatile compounds of K. grandifoliola (KgO) and K. senegalensis (KsO) oil, respectively. Caryophyllene-oxide (23.01%), isocaryophyllene (Z) (21.99%), and α-humulene (13.46%) were the main compounds identified in KgO, whereas in KsO they were caryophyllene oxide (14.85%), β-caryophyllene (43.59%), and α-humulene (15.72%). The volatiles were tested for cytotoxic activity against liver (HepG-2), breast (MCF-7), and colon (HCT-116) human cancer cell lines. K. grandifoliola and K. senegalensis oils displayed cytotoxic activity with IC50 (21.6, 26.1, and 37.6 μg.mL) and (61.1, 79.7, and 61 μg.mL), respectively. Sesquiterpene content of Khaya oils may contribute to their cytotoxic activity.